Extraction Of Ions Research Articles

Solid-liquid extraction for yttrium recovery using porous polymeric resin (XAD-7) functionalized with D2EHPA

The recovery of yttrium is proposed by applying a solid–liquid extraction process using di-2-ethyl hexylphosphoric acid (D2EHPA) as extracting agent. The extracting agents were supported on a macro porous polymeric resin XAD-7 (solid phase). Yttrium ions extraction and discharge tests were performed, firstly from a synthetic aqueous solution of 100 mg/L Y (liquid phase) at 25 °C with stirring. The effects of pH of aqueous solutions bearing yttrium, volume fraction of extracting agents and the solid/liquid (S/L) ratio on the yttrium recovery were studied. The most favorable conditions for yttrium ions extraction are: 20 vol% D2EHPA functionalized resin, pH = 1.5 and an S/L ratio of 10 mg/mL. The discharge of yttrium ions was done under the same conditions of extraction stage, using a 2 mol/L [H2SO4] as stripping solution. Up to 80% yttrium is extracted, while 75% yttrium is recovered in the striping solution. In all experiments, the reaction equilibrium is reached after 20 min, and the kinetics for the extraction stage was determined as a second-order model. Also, experiments were carried out to discharge the yttrium-loaded resins, and it has been determined that the best pH value to strip the Y ions is 1.5. Cyclic tests of extraction and discharge for yttrium ions show that the functionalized resin can work at least five cycles without decreasing its efficiency. Finally, the proposed process was tested in a real solution with Y ions from a waste fluorescent lamp powder leached in H2SO4, demonstrating the ability to effectively recover yttrium, separating it from various metals from the studied residue.

Extraction of Na+ ions by dibenzo-18-crown-6 in biphasic aqueous systems of ionic liquid and chloroform

The molecular dynamics simulations were carried out to explore the extraction of Na+ ions in the ionic liquid (IL)–water, chloroform–water biphasic systems containing the crown ether: dibenzo-18-crown-6 (DB18C6) to compare organic solvents such as chloroform to ionic liquid (IL) as receiving solvent phase. The free DB18C6 was found to be highly interacted with IL as compared to chloroform. The Na+–DB18C6 complex interacts preferentially with IL at the interface. The complex has higher interaction energies with IL (-47.04 kcal/mol) as compared to chloroform (-0.11 kcal/mol). The large sharp peak height for the radial distribution function in Na+–DB18C6 complex suggests high stability and strong interaction. At the IL–water interface, it was observed that the Na+–DB18C6 complex had a lower self-diffusion coefficient (0.538 × 10−9 m2/s) than other species. The spatial distribution functions further indicated that the surfaces of Na+ were very closely distributed around the active sides of crown ether in the IL–water system whereas, in chloroform–water systems, it was distributed very far from the crown ether. The present results may help us to understand the role of solvents in heavy metal ion extraction and also in the future design of crown ethers and solvents.

REMOVAL OF CADMIUM IONS FROM AQUEOUS SOLUTIONS USING BURNT ROCK

Adsorption treatment of industrial wastewater and reservoir water from toxic metals can reduce the anthropogenic load on water bodies. The efficiency of using an adsorbent obtained on the basis of local mineral raw material, namely burnt rock from the Erunakovskoe coal deposit in the Kemerovo Region, to remove heavy metal ions from aqueous solutions is shown. The kinetics of cadmium ion extraction from aqueous solutions, the adsorption models of Freundlich, Langmuir and Dubinin-Radushkevich, and their significance for the description of heavy metal ion recovery from aqueous solutions using burnt rock were studied. The dependence of adsorption on the acidity (pH) of the medium has been established. A maximum adsorption capacity of 30 to 40 mg/g was achieved at pH 12.0. Chemical modification with alkali (NaOH) at pH 12 leads to an increase in the degree of cadmium ions extraction. Within the studied concentration range, the Freundlich and Langmuir isotherms are more consistent with the experimental data on the equilibrium adsorption of metal ions on burnt rock, compared to the Dubinin-Radushkevich model.

Continuous Extraction and Electrochemical Monitoring of Potassium Ions in a Plant Leaf Using a Wearable Ion Sensor

Continuous Extraction and Electrochemical Monitoring of Potassium Ions in a Plant Leaf Using a Wearable Ion Sensor

Experimental and simulation study on the backstreaming positive ions on the quarter-size negative ion source for CRAFT NNBI test facility

As an effective methods of plasma heating, neutral beam injection (NBI) systems based on negative hydrogen ion sources will be utilized in future magnetic-confinement nuclear fusion experiments. Because of the collisions between the fast negative ions and the neutral background gas, the positive ions are inevitable created in the acceleration region in the negative NBI system. These positive ions are accelerated back into the ion source and become high energy backstreaming ions. In order to explore the characters of backstreaming ions, the track and power deposition of backstreaming H+ beam is estimated using the experimental and simulation methods at NNBI test facility. Results show that the flux of backstreaming positive ions is 1.93 % of that of negative ion extraction from ion source, and the magnet filed in the beam source has an effect on the backstreaming positive ions propagation.

Menthol-Based (Deep) Eutectic Solvents: A Review on Properties and Application in Extraction.

In the last 10 years the interest in deep eutectic solvents (DESs) as a new class of green solvents has considerably increased. The emergence of numerous of hydrophobic DESs has stimulated intensive research into their application in extraction technologies, including sample preparation. As the properties of such systems are highly dependent on the properties of their components (hydrogen bond donors and acceptors) and can be finely tuned, DESs can be successfully used for the extraction of both metal ions and organic substances, including biomolecules. Despite the rapidly increasing number of publications on the use of DESs as an extraction medium, including review articles, information on the extraction properties of DESs in terms of their chemical composition has not yet been summarized. This review covers available literature data on the physicochemical properties of menthol-based eutectic solvents and the results of their practical application as an extraction medium. Also, the appropriateness of using the term "DES" for all mixtures with melting points lower than the melting points of their components is discussed.

Activation-self-activation craft for one-step synthesis of GO-inbuilt mesopore-dominated N-doped hierarchical porous carbon in capacitive deionization capture of Ni(II)

Capacitive deionization (CDI) is considered a polar-promising technology to remove heavy-metal ions from wastewater. Herein, a green activation-self-activation strategy was exploited to build graphene (GO)-inbuilt mesopore-dominated N-doped hierarchical porous carbons (ENHPCs) using sodium lignosulfonate (SLS) as carbon sources/self-activators. Different from SLS self-activation and K2C2O4-SLS activation-self-activation, ENHPCLKG gained via GO-mediated K2C2O4-SLS activation-self-activation showed suitable mesopore-dominated micro-mesoporous structures with high surface area of 1795.5 m2/g, large mesoporous volume of 0.87 m3/g, 3.65 % N-doping and excellent conductivity. Its unique hierarchical porous structure and abundant active sites facilitated the ion rapid insertion and extraction. When utilized to capture low-concentration nickel (Ni2+) ions, ENHPCLKG delivered splendid salt removal capacity of 17.86 mg/g, rapid average salt removal rate of 0.99 mg/g/min and standout cycle stability. Meanwhile, ENHPCLKG was further extended to remove NaCl, MgCl2, CaCl2 and Ni-containing wastewater, showing superior CDI property. Moreover, the recycled ENHPCLKG (10th) taken to eliminate indomethacin (IDM) depicted a splendid adsorption capacity. This work proved the significant applicant potential of the novel and green ENHPCLKG for disposing of Ni2+ ions via CDI technology.

A Hydrophobic Deep Eutectic Solvent for Nuclear Fuel Cycle: Extraction of Actinides and Dissolution of Uranium Oxide

AbstractHydrophobic Deep Eutectic Solvents (DESs) have been attracting attention for metal ion extraction in solvent extraction process due to their favorable properties. A Trioctyl phosphine oxide (TOPO) and Thenoyl trifluoroacetone (HTTA) based hydrophobic DES was synthesized and characterized by FTIR and NMR spectroscopy. Actinide ions ( UO22+, Pu4+ and Am3+) and Eu3+ ion extraction was carried out using the DES which shows that it extracts these metal ions from aqueous nitric acid medium depending upon the molarity of nitric acid. At higher molarity of nitric acid (>5 M) the extraction becomes insignificant only for trivalent metal ions and open up the possibility to selectively strip trivalent metal ions from tetravalent and hexavalent ions. This DES was also used for dissolution of uranium oxide (UO3). The dissolution kinetics was studied and it was shown that oxide was dissolved within an hour at 80 °C. The maximum solubility of UO3 in DES was measured and found to be 130±5 mg/mL which is one of the highest reported solubility of UO3 in ILs and DES. The species of uranium which is formed in situ in DES was ascertained to be UO2(TTA)2.TOPO after dissolution of UO3 as supported by FTIR and NMR (1H and 31P) investigations.

Influence of anion structure on volumetric properties of dilute binary systems containing carboxylate functioned trihexylammonium ionic liquids in toluene / dodecane

We are actively involved in synthesis of hydrophobic ionic liquids, their volumetric behaviour in various solvents of different polarity and their application in metal ions extraction from water. In continuation of previous work, we are presenting new protic ionic liquids (PILs) containing Trihexylammonium cation and carboxylate anions namely Trihexylammonium propionate [THA][Pro] and Trihexylammonium pentanoate [THA] [Pent]. The simultaneous measurements of densities, ρ along with speeds of sound, u for binary systems of [THA][Pro] and [THA][Pent] in toluene and in dodecane were collected. The measurements were carried out in dilute concentrations range of PILs, at 0.1 MPa and different temperatures from 293.15 K to 328.15 K. The experimental values of densities, ρ and speeds of sound, u, were utilized to obtain calculated values of apparent molar properties: Vϕ (apparent molar volume) and Ks,ϕ (apparent molar isentropic compressibility). It is observed that the apparent molar properties of investigated systems are quite sensitive to variation in temperature, solvent and anion’s structure of PILs. The values of Vϕ and Ks,ϕ increases with each increment in studied temperature and when toluene was replaced by dodecane as a solvent in the system. The each addition of –CH2 group in anion chain of PILs leading to increase Vϕ whereas decrease with concentration of PILs in the binary system. The limiting values of apparent molar volume, Vϕ∞ and apparent molar isentropic compressibility, Kϕ∞ were also reported. The strength of interactions between PIL-PIL and PIL-solvent in studied binary systems was explained by Sk and Sv parameters. The PILs + dodecane systems exhibit greater interaction between PILs and solvent than binary systems of PIL + toluene.

Sorption of copper (II) ions by a composite sorbent based on chitosan and montmorillonite

A composite sorbent based on chitosan and montmorillonite has been developed for the extraction of heavy metal ions from aqueous solutions. The optimal chitosan / montmorillonite ratio for obtaining sorbent granules has been determined. Equilibriumkinetic studies of the process of copper (II) ions extraction in the heterophase system "aqueous solution of metal sulphate - modified sorbent" have been carried out.The treatment of sorption isotherms of copper (II) ions by the initial chitosan and a chitosan based composite according to the Langmuir equation made it possible to determine the maximum sorption capacities of these materials (А∞). It has been established that A∞ of the chitosan/montmorillonite composite sorbent exceeds the maximum sorption capacity for the original chitosan by more than two times.The effect of pH on the sorption of copper ions by chitosan-based sorbents is due to the competition of metal cations and protons for sorption sites. In the course of competitive chemisorption, protons deactivate amino groups - the main sorption centers, converting them into an inactive, H-salt form, which leads to a decrease in the sorption capacity of chitosan in relation to copper ions.Changes in the composition of the modified sorbent compared to the original chitosan are confirmed by infrared spectroscopy data. Microscopic studies using the method of scanning electron microscopy show the presence of changes in the surface structure of chitosan granules when montmorillonite is introduced into the composition of the sorbent.

Constant current pulsed power supply for long pulse arc discharge positive hydrogen ion source.

The simplest way to produce high density hydrogen plasmas is to form an arc between the arcing electrode and the plasma chamber (cathode). For arc-based hydrogen plasma generation, a pulsed power supply that delivers 2 ms-long constant current pulse has been developed. This pulsed power supply employs a high frequency buck converter topology with a nonlinear filter inductor. This paper describes the development and testing of a constant current pulsed power supply that operates at 50A and 550V with a pulse width of 2ms and a pulse repetition rate of 2Hz. By changing the arc current, the arc impedance and the positive hydrogen ion current were also measured. The extraction of positive hydrogen ions was carried out using a three-electrode extraction design, which results in a current of 80 mA of positive hydrogen ions at an energy of 50keV.

Covalent organic frameworks based hierarchical porous hybrid monolithic capillary: Synthesis, characterization, and applications in trace metals analysis

The preparation of hierarchical porous monolithic column with high covalent organic frameworks (COF) loading and micropores accessibility is challenging due to the easy aggregability and sedimentation of COFs. Herein, a novel strategy based on high internal phase emulsion (HIPE) polymerization was proposed for preparing COF hybrid capillary monolithic column with hierarchical porosity. COFs with different frameworks including imine COFs (COF-OMe, COF-F and COF-SH), triazine COF (CTF-1) and boron-based COF (COF-5) were selected to investigate the universality of the preparation strategy. The presence of COF in the monolithic capillary was confirmed by scanning electron microscope, X-ray diffraction and fourier transform infrared spectroscopy. Nitrogen adsorption/desorption experiments and thermogravimetric analysis showed that the prepared COF hybrid monolithic capillary exhibited high COF loading (e.g., 28.7% for COF-SH) and accessibility (e.g., 98.5% for COF-SH), mainly due to the thin walls of void-window structures originated from polymerization of HIPE. The successful preparation of water-stable COF-F, COF-OMe, COF-SH and CTF-1 hybrid monolithic columns demonstrated the proposed synthesis strategy is universal to water-stable COF without tedious optimization of dispersion system, effectively avoiding the sedimentation of COF in pre-polymerization solution. Then, the sulfhydryl-modified COF hybrid polymer (poly(COF-SH-HIPE)) monolithic column was evaluated for the extraction of heavy metal ions, and a method based on poly(COF-SH-HIPE) monolithic capillary microextraction on-line coupled with inductively coupled plasma mass spectrometry detection was developed for analysis of trace Cd, Hg and Pb in human fluid samples.

Hydrothermal Synthesis of Highly Effective Carbon Sorbent Based on Renewable Resources

The synthesis of new sorption materials by hydrothermal carbonization of sunflower meal (HTS) with the addition of graphene oxide (GO) and subsequent carbonization (C) was developed. To assess the morphological and phase changes during carbonization, the materials were characterized by scanning electron microscopy and IR spectroscopy. According to the results obtained, carbonization promoted the development of latent porosity, as well as a decrease in the amount of oxygen-containing and alkyl groups. Kinetic sorption studies were also carried out on the example of the Pb+2 ions and organic dye molecules – methylene blue (MB), extraction. The experiment results showed that the adsorption capacity of HTS, HTS/C, HTS/GO, and HTS/GO/C composites for the Pb+2 ions extraction was 82.9; 108.6; 168.9; 148.3 mg/g, respectively; and for MB molecules – 1481.8; 1601.1; 1920.3; 2283 mg/g, respectively. It was found that during adsorption of MB molecules, the carbonization effects significantly on the contact time. Carbonized samples show high sorption activity. The equilibrium contact time fort them was 15 min, while for non-carbonized samples it was 60 min. The equilibrium time during the Pb+2 ions adsorption was 60 min for all samples. The adsorption kinetics was described using the following models: pseudo-first order, pseudo-second order, the Elovich model, and intraparticle diffusion. It was found that the adsorption process is limited by the chemical exchange reaction and proceeds in a mixed-diffusion mode.

Efficient catalytic extraction of metal ions in some Persian Gulf algae samples using Fe3O4@SiO2-(3-chloropropyl) trimethoxysilane-l-cysteine nanocomposite and clustering of water samples according to alga metal pollution

Efficient catalytic extraction of metal ions in some Persian Gulf algae samples using Fe3O4@SiO2-(3-chloropropyl) trimethoxysilane-l-cysteine nanocomposite and clustering of water samples according to alga metal pollution

Effect of chemical modification of cotton cellulose by anthranilic acid on the sorption of Cu(II) and Fe(II) ions

The authors modified cotton cellulose with anthranilic acid to obtain a new sorbent capable of efficient extraction of heavy metal ions from aqueous solutions. We conducted the modification in two stages: at the first stage, we obtained dialdehyde cellulose by oxidation of cellulose with sodium metaperiodate; at the second stage, we treated dialdehyde cellulose with anthranilic acid to obtain a ready-made sorbent. The authors determined the optimum conditions for modifying cotton cellulose to achieve maximum sorption of iron(II) and copper(II) ions. We studied the equilibrium-kinetic characteristics of the original and modified cotton cellulose. Also, we have processed the results of the kinetic experiment within the framework of pseudo-first- and pseudo-second-order kinetics models. We selected sorption isotherms, processed them within the framework of the Langmuir model, and determined the values of the ultimate sorption capacity (A∞). The modification of cotton cellulose enables to increase its sorption capacity significantly. According to the results, the A∞ of the modified sorbent is about 4-5 times higher than the ultimate sorption capacity of native cotton cellulose to Cu(II) and Fe(II) ions. In contrast, we obtained and compared the IR spectra of anthranilic acid-modified cellulose and native cellulose. Additionally, we obtained SEM images of the modified sorbent and the native cotton cellulose surface structure.

Construction of nitrogen-doped carbon cladding LiMn2O4 film electrode with enhanced stability for electrochemically selective extraction of lithium ions

Construction of nitrogen-doped carbon cladding LiMn2O4 film electrode with enhanced stability for electrochemically selective extraction of lithium ions

Water-Floating Hydrogel Polymer Microsphere Composites for Application in Hydrological Mining of Cu(II) Ions.

Innovative materials and technologies capable of extraction and recovery of technologically relevant metal ions from various water sources, such as lakes, oceans, ponds, or wastewater reservoirs, are in great demand. Polymer beads are among the most well-known solid-phase adsorbents and ion exchangers employed in metal ion recovery. On the other hand, hydrogels are an emerging platform for producing innovative adsorbents, which are environmentally friendly and biocompatible materials. In this work, we take advantage of both technologies and produce a new type of material by loading nanostructured polymer microsphere adsorbent into a PVA matrix to obtain a hydrogel polymer microsphere (HPM) composite in the form of a block. The main role of the poly(4-vinylpyrridine-co-methacrylic acid) microspheres is to adsorb metal ions, such as Cu(II), from model water samples. The secondary role of these microspheres in the hydrogel is to change the hydrogel morphology by softening it and stabilizing it under a foam-like morphology. The foam-like morphology endows these composites with the capability of floating on water surfaces. In this work, we report, for the first time, an HPM composite capable of floating on water surfaces and extracting Cu(II) ions from model water samples. This could enable more environmentally friendly hydrological mining technologies by simply deploying adsorbents on water surfaces for metal ion extraction and recovery, thus eliminating the need for water pumping and mechanical processing steps.

Dielectric barrier discharge as bipolar ion source for aerosol charging: Application to filtration, thin film, and aerosol size measurement

We have investigated the potentialities of dielectric barrier discharges (DBD) for aerosol electro-processing with a special focus on ion production and aerosol charging for deposition (filtration and materials) and aerosol measurement tools. The advantages and drawbacks of aerosol injection downstream or upstream of the discharge are compared according to the application. The main parameters that control ion production and transport are investigated based on post-discharge ion current measurements. Post-DBD aerosol chargers are compared for submicron particle size measurements based on aerosol bipolar charging and electrical mobility analysis. Finally, the principle of counterflow extraction of bipolar ion from an atmospheric pressure DBD is established from upstream measurements of positive and negative ion fluxes in air, without neither ozone (<0.1 ppmv) nor nanoparticles.

Evaluation of a Phosphinate Functionalized Ionic Liquid for the Separation of Nb and Ta from Nitric Acid Feed Conditions.

A 'green' single-step separation process, involving a phosphonium phosphinate functionalized ionic liquid (FIL) in C8mim·NTf2, has been developed for highly encouraging improvements in the mutual separation of Nb and Ta with a maximum separation factor of ∼48 at 2 M nitric acid. The separation factor in C4mim·NTf2 was found to be somewhat lower compared to that seen in C8mim·NTf2. In C8mim·NTf2, the extraction proceeded via the neutral NbOF3(R4P+)(R2POO-) and TaOF3(R4P+)(R2POO-) species predominated by a 'solvation' mechanism at 2 M HNO3, where both the cationic and anionic parts of the FIL took part in the metal ion extraction. However, in the case of C4mim·NTf2, the extraction proceeded via a cation exchange mechanism involving the mono-positive species viz. [NbO(R2POO-)2]+IL, [TaO(R2POO-)2]+IL. Only the phosphinate group of the FIL was directly involved in the binding to the metal ion. The charge neutrality was maintained by the exchange of the C4mim+ ion from the ionic liquid phase to the aqueous phase. The processes were spontaneous, exothermic involving outer sphere complexation. The radiolytic stabilities of the C8mim·NTf2-based solvent systems were poorer than those of the solvents based on C4mim·NTf2. Aqueous solutions of EDTA-guanidine carbonate or DTPA-guanidine carbonate showed promising back extraction ability though three contacts of these organic phases were required for more than 99.99% stripping of the metal ion. The reusability of these solvent systems was evaluated. After four consecutive cycles, a maximum of only 8% reduction in the extraction efficiency of Ta was noticed, while for Nb it was less than 4% for Nb.

Pickering Emulsion Polymerization Technology─Toward Nanostructured Materials for Applications in Metal Ion Extractions from Wastewaters

Pickering Emulsion Polymerization Technology─Toward Nanostructured Materials for Applications in Metal Ion Extractions from Wastewaters